﻿/*******************************************************************************
 * Copyright (c) 2007
 * Sergey Berezin, Dmitry Voitsekhovskiy
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms,
 * with or without modification, are permitted provided
 * that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * - Neither the name of the Moscow State University nor the names
 * of its contributors may be used to endorse or promote products
 * derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 ******************************************************************************/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Linq.Expressions;

namespace Faml.Operations
{
    [OperationContainer]
    public class GenericUnfold
    {
        [OperationName("unfold")]
        public static T[,] Unfold<T>(int n, int m, Expression<Func<int, int, T>> func)
        {
            T[,] values = new T[n, m];

            Delegate del = func.Compile();


            Func<int, int, T> gen = func.Compile();

            for (int i = 0; i < n; i++)
                for (int j = 0; j < m; j++)
                {
                    values[i, j] = gen(i, j);
                }

            return values;
        }

        [OperationName("unfold")]
        public static T[,,] Unfold<T>(int n, int m, int w,Expression<Func<int, int, int, T>> func)
        {
            T[,,] values = new T[n, m, w];

            Delegate del = func.Compile();


            Func<int, int, int, T> gen = func.Compile();

            for (int i = 0; i < n; i++)
                for (int j = 0; j < m; j++)
                    for(int k=0;k<w;k++)
                {
                    values[i, j,k] = gen(i, j,k);
                }

            return values;
        }

        [OperationName("unfold")]
        public static T[] Unfold<T>(int n, Expression<Func<int, T>> func)
        {
            T[] values = new T[n];

            Func<int, T> del = func.Compile();
            for (int i = 0; i < n; i++)
            {
                values[i] = del(i);
            }

            return values;
        }

        [OperationName("unfold")]
        public static T[] Unfold<T>(Expression<Func<int, T>> func, int n)
        {
            return Unfold(n, func);
        }

        

        [OperationName("unfold")]
        public static T[,] Unfold<T>(int n, Expression<Func<int, T[]>> func)
        {
            Func<int, T[]> f = func.Compile();

            T[] fArray = f(0);

            int m = fArray.Length;
            T[,] values = new T[n, m];

            for (int i = 0; i < n; i++)
            {
                if (i > 0)
                    fArray = f(i);
                if (fArray.Length != m)
                    throw new Exception("unfold: inner function must return arrays with same length");

                for (int j = 0; j < m; j++)
                {
                    values[i, j] = fArray[j];
                }
            }

            return values;
        }

        [OperationName("unfold")]
        public static T[,] Unfold<T>(Expression<Func<int, T[]>> func, int n)
        {
            Func<int, T[]> f = func.Compile();

            T[] fArray = f(0);

            int m = fArray.Length;
            T[,] values = new T[m, n];

            for (int i = 0; i < n; i++)
            {
                if (i > 0)
                    fArray = f(i);
                if (fArray.Length != m)
                    throw new Exception("unfold: inner function must return arrays with same length");

                for (int j = 0; j < m; j++)
                {
                    values[j, i] = fArray[j];
                }
            }

            return values;
        }
    }
}
